Circuit-breaker and switch.



G. A. BURNHAM. cmcun BREAKER AND svincu.

APPLHZATION FILED APR. 4, I916.

1 ,269, 1 56. Patented June 11, 1918. v

,UNITED STATES PATENT OFFICE.

GEORGE A. BURNHAM, OF SAUGUS, MASSACHUSETTS, ASSIGNOR TO SEARS B.CONDIT, 33.,

OF BROOKLINE, MASSACHUSETTS.

Application filed April 4, 1916.

To allwkom it may concern:

Be it known that I, GEORGE A. BURNHAM, a citizen of the United States,residin at San us,-in the county of Essex and rtate I to open,particularly in large circuit-breakers, and,-as a result, considerablepower is required to move said latch to disengage the operating= member.The tripping-coil is usually made {of proportions larger than need be,in order that it may operate to move the latch,'upon an overload orother abnormal condition of the circuit, but, in case it shouldfail'and' consequently fail to disen gage the operatin g-member, theresult would be disastrous.

Furthermore, in the manufacture of circhit-breakers, both theoperating-member and the latch-are usually pivotally suported more orless loosely to insure the correctengagem'ent of the contacts. Onaccount of this looseness, both elements wabble more or less=on theirsupports, and when in certain relative positions, bind or cramp, and insuch event, movement of the latch is restrained.

This invention has for one of its objects certain improvements in thelatch-engaging means, and also in the latch-supportingmeans, whichenable the latch to be moved easily by a tripping-coil of normalproportions. and insure a prompt or reliable operation of thecircuit-breaker; and has for another object, the provision oflatch-engaging means, and also latch supporting means which admit of awabbling movement of the latch and of the operating-member, yet

avoid binding or cramping action.

My improved latch-engaging means and latch-su porting means, eitheralone, add materiafiy to the freedom of motion of the latch, but 1?prefer to employboth means.

Specification of Letters Patent.

Patented June 11, 1918.

Serial No. 88,803.

Figure 1 is a side elevation of a circuitbreaker embodying thisinvention.

Fig. 2 is a fragmentary sectional detail, the latch being shown in plan.

Fig. 3 is an enlarged side elevation of the latch and associatedlatch-engaging element and supporting-means.

Fig. 4 is a fragmentary view, in front elevation, of theoperating-member.

Fig. 5 is a vertical sectional detail of the latchengaging element.

Figs. 6 and 7 are vertical sectional views of an end-portion of thepivot-shaft of the latch and bearings therefor, in different relativepositions.

The circuit-breaker here shown comprises an arm 10, pivoted at 11, andbearing a briding contact-member 12. adapted to engage contact-members13, 14; and an auxiliary contact-member 15, adapted to engagecontact-members 16, and another contactmember 17 adapted to engage acontactmember 18. A link 19 loosely connects said pivoted arm 10, withan arm 20, of a bellcrank which is pivoted at 21, the other arm 22, ofwhich bell crank is arranged to serve as and constitute theoperating-member or handle.

When the operating-member or handle 22 is pressed down, thecircuit-breaking element is closed, and said element is held closed by alatch 30, engaging said handle, but when the latch is, moved todisengage the handle, said circuit-breaking element is permitted toopen, hence it is biased to open position.

This structure, however, is intended merely to typify a general form ofcircuit-breaker, to which my invention is applicable.

The operating-member 22 has a hole 24 through it, see Fig. 1, in whichis arranged transversely a rod 25, and on said rod there is looselymounted a ring 26, see Figs. 3 and 5, having an outer peripheral oovewhich receives a set of balls 27, which latter are held in place and inspaced apart relation by a. separating-ring 28, and an outer ring .29 isloosely arranged on said balls, it havring 26, are all otatable freelyabout a horizontal axis and serve as the latch engagingelemeut. Theouter rin 29 is free to oscillat slightly, or to a limited extent, aboutan axis at right angles to its horizontal axis of rotation, asillustrated in Fig. 5, yet in any angular position, it may occupy,relative to the rod 25, is adapted to freely rotate.

30 represents the latch which is pivoted at 31. Its latch-formed endengages the outer periphery of the ring 29, and when moved either upordown, acts to move-the ring rotarily in a corresponding direction, andthe latter being supported on ball bearings, is freely revoluble, sothat movement of the latch is not restrained, even when exertingconsiderable pressure in the ring.

As here shown, the latch-formed: end-portion of the latch has twoengaging faces 32 and 33, arranged at right angles withrela tion to eachother ndadapted to engage tangentially the ring 29, the engagingface 33being adapted to ride along upon orwith the rotatable-engagingelement,,and the engaging face 32,- limiting the downward movement ofthe latch. Said latch-formed end also has an outer curved engaging-face34, adapted to be engaged by the rotatable latchengagin element when thehandle is moved into late-engaging position. The pivot '31 of the latchis arranged in a'housing 40, which is supported by a pivot-shaft 42.Said housing corn rises a pair of spacedapart side plates 4., 41, a topcross bar-45, and a bottom cross bar 46', all integrally formed orjoined together. The pivot31 forthe latch is arranged between the sideplates near the rear of the housing. The pivot shaft 42 is dividedintermediateits ength, and the housing is arranged between its componentparts and is joined to the side plates 41, 41, in front of the pivot 31so that the housing projects in ear of the pivot-shaft. The latch 31 hasa lug 47 extended downwardly, which engages the bottom crossbar 46, andmovement of the latch is caused by a movement of the housing andpivot-shaft to which it is connected. The cross-bar 45 serves to limitupward movement of the latch.

Said cross-bar 46 is arranged in the path of movement of an arm 50, of abell-crank lever, which is pivoted to the frame, the other arm 52 ofsaid lever bearing the armature 53 of the tripping-coil 54. Thisarmature is normally retracted, but when attracted, upon energizationofthe trippingcoil, the arm 50 will be moved to strike the cross-bar 46of the housing, and will move the housing on the axis of'the,pivot-shaft 42, and said cross-bar will, in turn, by-engagement with thelug 47, on the latch", lift said latch on its pivot 31 to disengage theengaging-element on the operating-member.

To limit the oscillating movement of the pivot-shaft 42, there are fixedto said shaft two dogs 56, and 57, which are extended radially, one ofwhich, as 56, is adapted to engage one edge of a plate 58, secured tothe- 'frame, and the other, as 57, is adapted to ngage rn other edge ofthe plate 58. The dog'fifi limits the movement of the shaft in airection to permit the latch to engage the latch-engaglng element, andthe dog 57 limitsthe movement of the shaft in the other direction. Thepivot-shaft 42 has self-aliming bearings engaged.- by its endrjokmml'Thisisof particular advantage in case of a multipole circuit-weaken.wherein the pivot-shaft 42 is extended. toinolude allof the breakingelements, and is adapted for oscillation by the trip, coil of; any ofthe breaking elements, es'insuch case, .tvhe circuit-breaker is;usuallyshipped knock-down, and? adapted c he sets up, upon arriving at.its destination.

Referring to. Figs. 6 and 7, the pivot- Shafts: of the breaking elementshave their adjacent end-journals adapted! to. be-conneeted: together,as, for instance, they may have threaded sockets to ireceive thethreaded ends 0d connecting rods 7Q, which-rods are connected togetherby a coupling end-journals 60 oi the pivotsshait 42 are receivedi-nzcircular in inner rings 61, whichareior'medwiithrperipheralgrooves B5 to receive Balls .62, which-arre heldin. place therem in 'spaced aartvelation, hyr'se aating rings-GB; outer rings 64' has .ng

1mm!" peripheral: onreceiving: grooms are arranged 'onithe balls, andsaidrou'ter rings.

have -flat outer *pfilii pllwiesyadflrptaimgr themto be set incircurlarrecesses. in! the summrtin frames. The; PlVOtrfihflefl'z isthussuppented at its ends in ball-bearing supporte and hence are .freelyrotatable 1nfireball-hear ingelementsrhene shown. Furthermore,- theinner rings 61: are adapted to oscillate through short area: on axes atht angles to the axes 05- rotation of? thepivot-shaft,

thus admitting of. self alinement, of the piivotsshaftsg as; occasiondemands.

I claim 1. A circuit-breaker having a movable switch-member, anoperating-member for it,

locking meansfor said operatin -member,'

one ofthe component elements o which is adapted forangular movements andfor rotation in any: angular'positionfi it may occupy, and atrippmg oollcontrolling said loeldng-means 2. A circuit-breaker" having a {movableswitchmember, an-eperating-memberfor it, looking-means: for saidoperat'm -member, one of'the-componeiit elements -0 which is adaptedrotation and'is equip ed with a ball bearings; one member of wide isadapted for-angulanrotat'ion with iez-xpect to a stationary member, anda :trippingmoil controlling said locking means;

.3.-A circuit breaker having a movable 130 switch-member, anoperating-member for it, a latch, a trip-coil for the latch, a supportborne by the operating-member and a latchengaging element arranged onsaid support and adapted for angular movement with respect to itssupport and also for rotation in any position it may occu y.

4. A circuit-breaker aving a movable switch-member, an operating-memberfor it, a latch, a trip-coil for the latch, and a rotatablelatch-engaging element borne by the operating-member equi ped with aball bearing, one member of which is adapted for angular rotation withrespect to a sta tionary member.

5. A circuit-breaker having a movable switch-member, an operating-memberfor it, a latch, a trip-coil for the latch, and a latchengaging elementborne by the operatingmember, comprising a ring and a support on whichsaid ring is free to move rotarily, and also to oscillate about an axisat right angles to its support.

6. A circuit-breaker having a movable switch-member, an operating-memberfor it, a latch, a trip-coil for the latch, and a latchengaging elementborne by the operatingmember comprising a rod, an inner rin arrangedthereon having a peripheral allreceiving groove, a set of balls arrangedin said groove, a separating-ring for the balls, and an outer ringarranged on the balls, and free to rotate about the rod as an axis, andalso to move angularly with respect thereto.

7. In combination with a circuit breaker having a movable member and anoperating member therefor having latch engaging means, of a latch, apivot shaft, :1 housing for the latch arranged on said shaftintermediate the length thereof, a pivotal support for said latcharranged in the housing in the rear of the axis of the pivot shaft, anda tripping coil for the latch.

8. In a circuit-breaker having a movable switch-member, anoperating-member far it, a latch, a latch-engaging element on theoperating-member, a support for the latch comprising a pivot-shafthaving end-supports adapted for angular movements, and for free rotationin any angular position it may occu y.

In testimony whereof, I have signed my name to this specification, inthe presence of two subscribing Witnesses.

GEORGE A. BURNHAM.

Witnesses:

DANIEL M. SHIFFERT, HAROLD S. RAMBAY.

Uoplen of this patent may be obtained for in cent: each, by addressingthe Commissioner of rotontl, Washington, D. 0."

